• 한국통신학회논문지
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• 제27권5C호
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• pp.486-495
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• 2002

본 논문에서는 프레임 기반 패킷 전송 스케쥴링을 위한 지연 감축 방안을 제안한다. ATM과 같은 초고속 통신망은 사용자에게 대역폭과 패킷 지연과 같은 성능을 보장하여야 한다. 스케쥴링 방법에 있어 프레임 기반 구조는 사용자에게 요구되는 대역폭의 지원과 간단한 레이트-제어 방법을 제공하지만 나쁜 지연 특성을 가지게 된다. 본 논문에서 제안한 지연 감축 방법은 HRR (Hierarchical Round-Robin)과 같은 계층적 프레임 구조를 사용하지만 지연 특성을 좋게 하기 위해 고정된 우선순위를 갖는 라운드 로빈 방식을 사용하지 않고, 동적으로 우선순위를 변화시킴으로써 광대역과 협대역 연결간의 지연에 있어서의 불평등을 해소하였다. 해석적 비교 및 모의실험 결과 제안된 HFIFO 방법이 기존의 HRR과 같은 프레임 구조의 장점을 그대로 따르면서, 연결간 공정한 지연품질 제공하며 전체 지연 값을 줄일 수 있음을 알 수 있었다.

• 한국수학교육학회지시리즈A:수학교육
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• 제46권1호
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• pp.53-67
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• 2007

During the recent years at a middle level Engineering School located at the local areas in Korea, more than 20 percent of freshmen had failed at their first College Mathematics. In consequence, many of them had hard time to survive at their major curriculums. The purpose of this study is to look for the main reasons of their failure and suggest an alternation of the present curriculum. Using the responses to the questionnaires and placement test scores, we studied the characteristics of the students' Mathematical abilities and analyzed how they were related to their grades of the First College Mathematics at the end of the first semester. The mathematical ability of the students at the middle level Engineering School turned out to range from bottom to top even though most of them revealed their interests towards Mathematics. The students with low scores at the placement test were more likely to fail at their first College Mathematics. Thus we suggest that the school should open a new preparation course ahead of the First College Mathematics for those who achieve low scores at the placement test and also professors should write proper books and develop ways of teaching.

• Steel and Composite Structures
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• 제30권6호
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• pp.517-534
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• 2019

In this paper, the effects of inevitable out-of-plane defects on the postbuckling behavior of single-layered graphene sheets (SLGSs) under in-plane loadings are investigated based on nonlocal first order shear deformation theory (FSDT) and von-Karman nonlinear model. A generic imperfection function, which takes the form of the products of hyperbolic and trigonometric functions, is employed to model out-of-plane defects as initial geometrical imperfections of SLGSs. Nonlinear equilibrium equations are derived from the principle of virtual work and variational formulation. The postbuckling equilibrium paths of imperfect graphene sheets (GSs) are presented by solving the governing equations via isogeometric analysis (IGA) and Newton-Raphson iterative method. Finally, the sensitivity of the postbuckling behavior of GS to shape, amplitude, extension on the surface, and location of initial imperfection is studied. Results showed that the small scale and initial imperfection effects on the postbuckling behavior of defective SLGS are important and cannot be ignored.

• 로봇학회논문지
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• 제17권4호
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• pp.417-424
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• 2022

In this paper, the developed trunk cargo unloading automation system is introduced, and the RGB-D sensor-based box loading situation recognition method and unloading plan applied to this system are suggested. First of all, it is necessary to recognize the position of the box in a truck. To do this, we first apply CNN-based YOLO, which can recognize objects in RGB images in real-time. Then, the normal vector of the center of the box is obtained using the depth image to reduce misrecognition in parts other than the box, and the inner wall of the truck in an image is removed. And a method of classifying the layers of the boxes according to the distance using the recognized depth information of the boxes is suggested. Given the coordinates of the boxes on the nearest layer, a method of generating the optimal path to take out the boxes the fastest using this information is introduced. In addition, kinematic analysis is performed to move the conveyor to the position of the box to be taken out of the truck, and kinematic analysis is also performed to control the robot arm that takes out the boxes. Finally, the effectiveness of the developed system and algorithm through a test bed is proved.

• 한국식생활문화학회지
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• 제13권3호
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• pp.169-182
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• 1998

This study was conducted to investigate the consumers' Dining-out preference and behavior for the chilled meat consumption strategy . A total of 328 persons in Seoul, Kyunggi areas were selected by stratified random sampling method and were responded to this study questionnaire which was composed of six parts with 65 statements about chilled meat consumption. 1. The frequency of Dining-out is characterized that 'once a month' is the highest pattern of consumers(46.3%) : In that cases, the married people showed 'once a month'(52.7%) and 'once biweekly'(23.3%), but the unmarried people showed the more frequent pattern as 'once a week'(27.3%) and 'twice a week'(27.3%). And the frequency of Dining-out in relation with the education level revealed that 'the graduate people' are the highest (37.5%). 2. Generally the first food for the Dining-out is 'Kalbi'(26.2%), and the others were 'pork grilling','chilled meat grilling','fish sasimi','chinese foods','pizza' etc.... But there were some variation in relation with incomes and housing types: For the agriculture/physical labor class, they prefers the 'pork griling'(25.0%), the office work class prefers the 'Kalbi' For the house-owner group, they prefers the 'Kalbi', but the house-renting/lodging group, they prefer the 'chinese food' or 'pork grilling' etc.... 3. In choosing the Dining-out place,'quality of food'(54.3%) and 'hygiene'(21.0%) were rated as the first important factor. 4.'Soups', 'Noodles' and 'Cooked rice in casserole' were chosen as good lunch menu : for male, they prefer the 'Soups', but females prefer 'Cooked rice in casserole'. 5. People with commercials/services(44.7%) and agriculture/physical labor(50.0%) ate their lunch in private restaurant, but peoples in the office work(57.0%)/public service personnel(70.4%) and industry use refectory; and it showed significant difference. 6. Consumers prefer the chilled meat as a Dining-out menu, but they didn't recognize the difference between chilled meat and frozen meat 7. For Dining-out menu, many people proper the beef, but the price of beef was so high than pork, agriculture/physical labor class choose the pork grilling instead of beef : commercials/services/office worker prefer the beef chilled meat . 8. The first admirable cooking method for chilled meat is direct radiation grilling with charcoal and many of consumers prefer tender, marbling, some chewy and juicy, flavor, soft as a quality of meat but physical labor class prefer the some tough and chewy texture.

• 한국가축번식학회지
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• 제27권2호
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• pp.163-167
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• 2003

본 연구는 미경산돈의 첫 발정과 종부시 품종에 따른 체중, 연령, 체장, 체고, 흉위, 등지방 두께, estradiol-l7$\beta$, cortisol 그리고 progesterone 농도에 미치는 영향을 조사하여 앞으로 돼지 번식능력 향상을 위한 기초자료를 제공하고자 실시하였다. 본 연구에 공시된 듀록, 랜드레이스, 요크셔 미경산돈은 충남축산위생 연구소 산하 축산시험장에서 2000년부터 2002년까지 생산한 자돈을 선발하고 육성하여 이용하였다 미경산돈의 첫 발정과 종부시 듀록종이 랜드레이스종이나 요크셔종 보다 체중이 더 무거웠고 연령이 많았으며, 흉위도 컸다. 첫 발정과 종부시 체장은 품종간에 차이가 없었고, 체고는 듀록종과 요크셔종이 랜드레이스종에 비하여 높았다. 첫 발정시 등지방 두께는 요크셔종, 듀록종 그리고 랜드레이스종 순으로 얇았으며, 첫 종부시에는 차이가 없었다. 미경산돈의 첫발정시 혈청 estradiol-l7$\beta$의 농도는 랜드레이스종이 45.0 pg/ml로 요크셔종의 27.4pg/ml 이나 듀록종의 21.8 pg/ml 보다 높았으나 첫 종부시에는 18.5-31.9 pg/ml로 품종간에 차이가 없었다. 혈청 cortisol의 농도는 첫 발정과 종부시 듀록종이 랜드레이스종이나 요크셔종에 비하여 높게 나타나 품종간에 차이를 나타내었다. 혈청 progesterone의 농도는 첫 발정과 종부시 품종간에 차이가 없었다.

• 대한물리의학회지
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• 제11권2호
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• pp.103-114
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• 2016

PURPOSE: The purpose of this study was first to develop a Korean version of pediatric functional muscle testing for children with a motor developmental disorder who have a communication problem and who are aged below five years, and also to verify the content validity. METHODS: First, the preliminary study was conducted to verify the reliability of pediatric functional muscle testing, developed by Venita in Korea. Based on the results of the study, the primary evaluation items were selected and modified. Second, the first test of content validity was conducted through a panel discussion, and a second investigation of content validity was carried out by utilizing the Item Content Validity Index (I-CVI). In this study, we selected only 0.78 or more items from I-CVI. RESULTS: Based on the results of the preliminary study, 19 primary evaluation items were selected. Based on the results of the first and second content validity tests, 15 tertiary evaluation items for the Korean version of pediatric functional muscle testing were determined. CONCLUSION: This study developed a new Korean version of pediatric functional muscle testing and suggested that it will be a useful tool to measure muscle strength for Korean children with a motor developmental disorder and a communication problem, aged below five years.

• Journal of Microbiology and Biotechnology
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• 제34권9호
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• pp.1789-1802
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• 2024

The purpose of this study is to investigate the effects of non-obese MAFLD on the gut microbiota and metabolic pathways caused by high-temperature processed meals. It was decided to divide the eighteen male Sprague-Dawley rats into three groups: the control group, the dry-fried soybeans (DFS) group, and the high-fat diet (HFD) group. Following the passage of twelve weeks, a series of physical, biochemical, histological, and microbiological examinations were carried out. There were distinct pathological abnormalities brought about by each diet. The DFS diet was found to cause the development of fatty liver and to demonstrate strong relationships between components of the gut microbiota, such as Akkermansia and Mucispirillum, and indices of liver health. Diet-induced changes in the gut microbiome have a significant impact on liver pathology in non-obese patients with metabolically altered liver disease (MAFLD), which suggests that dietary interventions that target gut microbiota could be used to manage or prevent the illness.

• 대한수의학회지
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• 제27권1호
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• pp.93-99
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• 1987

A study was conducted to observe the effects of dexamethasone sodium 21 phosphate injection in different amounts, intervals and times on the fluctuation of the parasitized erythrocytes in the peripheral blood of the T. sergenti carrier calves. A total of 31 calves including 15 Holstein and 16 Korean native male calves aged 6-12 months (125-300kg) was used. Results observed were as follows. 1. The calves injected 0.2mg/kg body weight two and three times in 48 hour intervals and 5 times in 24 hour intervals observed that 2 out of 2 heads, 3 out of 6 heads, and 4 out of 5 heads, respectively were substantially increased parasitized erythrocytes in the blood for 3-11 days after the first injection and continued to 2-10 days. 2. However, the calves injected once with 0.1mg/kg body weight and all control calves showed no visible change of the parasitized erythrocytes in the blood during the experimental period. 3. The animals injected over 2 times with 0.2mg/kg body weight tended to be decreased the number of erythrocytes, hemoglobin concentration and PCV for 2-3 days after first injection and continued about one week. 4. All animals injected the dexamethasone were observed the neutrophilic leukocytosis, eosinopenea and lymphopenea until 48 hours after injection.

• 한국조리학회지
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• 제13권4호
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• pp.243-255
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• 2007

This study carried out a survey which is related to food safety in food business in order to find out interest in food safety and to get awareness of food safety in food business. The research was done through surveys for the people in the Seoul Metropolitan area. 232 out of 250 answers were used in analyzing frequency, factor, $x^2$-test, and t-test through SPSS Win 12.0. There are three main factors of food safety in food business. The first is food borne illness(65.9%), the second is trans-fat(63.4%), and the third is remained agrichemicals(58.5%). Basically, women consider food safety more seriously than men do, and married women than unmarried women. Women were unsatisfied with the government's regulations than men were, married women than unmarried women. Women more consider awareness of food safety than men do, married women than unmarried women. Overall, unmarried women worried about their eating stuff seriously than any other group does. People consider food safety first, more and more these days, therefore, we need special management programs and regulations to focus on food safety and to support many studies about food safety.